diff --git a/frontend-web/src/pages/StudioNotebookDetailPage.tsx b/frontend-web/src/pages/StudioNotebookDetailPage.tsx
index 83d367f4..bfb7ea8b 100644
--- a/frontend-web/src/pages/StudioNotebookDetailPage.tsx
+++ b/frontend-web/src/pages/StudioNotebookDetailPage.tsx
@@ -6,11 +6,13 @@ import {
   AlertCircle,
   AlignLeft,
   ArrowLeft,
+  ArrowUp,
   BookOpen,
   Files,
   Globe,
   Loader2,
   Plus,
+  Square,
   X,
 } from "lucide-react";
 
@@ -119,6 +121,20 @@ function SourceCard({
   );
 }
 
+// ── 上传中占位卡片 ──────────────────────────────────────
+function PendingSourceCard({ title }: { title: string }) {
+  return (
+    <div className="group relative flex h-32 w-full flex-col justify-between rounded-2xl p-4 ring-1 ring-border/50 bg-muted/40 cursor-default">
+      <div className="flex size-10 items-center justify-center rounded-xl bg-background">
+        <Loader2 className="size-5 animate-spin text-muted-foreground" />
+      </div>
+      <div className="min-w-0">
+        <p className="truncate text-xs font-medium text-foreground">{title}</p>
+      </div>
+    </div>
+  );
+}
+
 // ── 来源骨架屏 ──────────────────────────────────────────
 function SourceCardSkeleton() {
   return (
@@ -137,6 +153,7 @@ function SourcesDialog({
   sources,
   isLoadingSources,
   selectedSourceIds,
+  pendingSources,
   onToggle,
   onDelete,
 }: {
@@ -146,6 +163,7 @@ function SourcesDialog({
   sources: SourceItem[];
   isLoadingSources: boolean;
   selectedSourceIds: number[];
+  pendingSources: Map<string, { id?: number; title: string }>;
   onToggle: (id: number) => void;
   onDelete: (id: number) => void;
 }) {
@@ -189,15 +207,26 @@ function SourcesDialog({
             <div className="grid grid-cols-4 gap-3">
               {isLoadingSources
                 ? Array.from({ length: 8 }).map((_, i) => <SourceCardSkeleton key={i} />)
-                : sources.map((src) => (
-                  <SourceCard
-                    key={src.id}
-                    item={src}
-                    selected={selectedSourceIds.includes(src.id)}
-                    onToggle={onToggle}
-                    onDelete={onDelete}
-                  />
-                ))}
+                : <>
+                    {Array.from(pendingSources.entries())
+                      .filter(([, s]) => !sources.some((src) => {
+                        const srcTitle = src.title ?? (src.document as { title?: string } | undefined)?.title ?? "";
+                        return srcTitle === s.title;
+                      }))
+                      .map(([taskId, s]) => (
+                        <PendingSourceCard key={taskId} title={s.title} />
+                      ))}
+                    {sources.map((src) => (
+                      <SourceCard
+                        key={src.id}
+                        item={src}
+                        selected={selectedSourceIds.includes(src.id)}
+                        onToggle={onToggle}
+                        onDelete={onDelete}
+                      />
+                    ))}
+                  </>
+              }
             </div>
             {!isLoadingSources && sources.length === 0 && (
               <p className="text-sm text-muted-foreground">暂无来源，请添加文件。</p>
@@ -231,6 +260,8 @@ export default function StudioNotebookDetailPage({
   // null = 显示历史线程列表；string = 显示该线程的聊天
   const [activeThreadId, setActiveThreadId] = useState<string | null>(null);
   const [citationChunkId, setCitationChunkId] = useState<number | null>(null);
+  // 轮询成功后待选中的来源标题集合（后端上传时不返回 id，等 sources 刷新后按标题匹配）
+  const pendingSelectTitlesRef = useRef<Set<string>>(new Set());
   const [threadsExpanded, setThreadsExpanded] = useState(false);
   const THREADS_LIMIT = 5;
   const [citationDoc, setCitationDoc] = useState<DocumentWithChunks | null>(null);
@@ -255,6 +286,22 @@ export default function StudioNotebookDetailPage({
       setSelectedSourceIds(sources.map((s) => s.id));
     }
   }, [sources, notebook?.id, initializedForNotebook]);
+
+  // sources 刷新后，将轮询成功的来源（按标题匹配）自动选中
+  useEffect(() => {
+    if (pendingSelectTitlesRef.current.size === 0) return;
+    const matched = sources.filter((s) => {
+      const title = s.title ?? (s.document as { title?: string } | undefined)?.title ?? "";
+      return pendingSelectTitlesRef.current.has(title);
+    });
+    if (matched.length > 0) {
+      setSelectedSourceIds((prev) => [...new Set([...prev, ...matched.map((s) => s.id)])]);
+      matched.forEach((s) => {
+        const title = s.title ?? (s.document as { title?: string } | undefined)?.title ?? "";
+        pendingSelectTitlesRef.current.delete(title);
+      });
+    }
+  }, [sources]);
   const citationRehypePlugins = useMemo(() => {
     const mapped = sources.map((s) => ({
       id: s.id,
@@ -299,6 +346,10 @@ export default function StudioNotebookDetailPage({
     }
   };
 
+  const handleStop = useCallback(() => {
+    void thread.stop();
+  }, [thread]);
+
   const handleSend = async (e: React.SyntheticEvent) => {
     e.preventDefault();
     const text = input.trim();
@@ -360,20 +411,17 @@ export default function StudioNotebookDetailPage({
         const data = await response.json() as { status: 'processing' | 'success' | 'failed' | 'error' };
         const taskStatus = data.status === 'failed' ? 'error' : data.status;
         if (taskStatus !== 'processing') {
-          // 任务完成，从轮询队列移除并刷新来源列表
+          // 先取出 source 信息，再从轮询队列移除
+          const source = pendingSources.get(taskId);
           setPendingSources((prev) => {
             const newMap = new Map(prev);
-            const source = newMap.get(taskId);
             newMap.delete(taskId);
-            if (source) {
-              if (taskStatus === 'success') {
-                // toast.success(`来源 "${source.title}" 处理完成`);
-              } else {
-                // toast.error(`来源 "${source.title}" 处理失败`);
-              }
-            }
             return newMap;
           });
+          // 仅成功时记录标题，等 sources 刷新后按标题匹配 id 并选中
+          if (taskStatus === 'success' && source?.title) {
+            pendingSelectTitlesRef.current.add(source.title);
+          }
           // 刷新来源列表
           void queryClient.invalidateQueries({ queryKey: ["studio", "sources"] });
           // 刷新 notebooks 数据以更新 source_count
@@ -383,7 +431,7 @@ export default function StudioNotebookDetailPage({
     } catch (error) {
       console.error(`轮询任务 ${taskId} 状态失败:`, error);
     }
-  }, [notebook?.id, queryClient]);
+  }, [notebook?.id, pendingSources, queryClient]);
 
   // 控制轮询 - 只在对话框打开时轮询
   useEffect(() => {
@@ -585,7 +633,6 @@ export default function StudioNotebookDetailPage({
                       disabled={isStreaming}
                       className="flex-1 bg-transparent text-[15px] text-foreground placeholder:text-muted-foreground outline-none disabled:opacity-50"
                     />
-                    {isStreaming && <Loader2 className="size-4 shrink-0 animate-spin text-muted-foreground" />}
                     {models.length > 0 && (
                       <Select value={selectedModel} onValueChange={setSelectedModel}>
                         <SelectTrigger className="h-7 w-auto shrink-0 gap-1 rounded-full border-0 bg-transparent px-2 text-sm text-muted-foreground shadow-none focus:ring-0 hover:bg-muted/60">
@@ -600,6 +647,24 @@ export default function StudioNotebookDetailPage({
                         </SelectContent>
                       </Select>
                     )}
+                    {isStreaming ? (
+                      <button
+                        type="button"
+                        onClick={handleStop}
+                        className="shrink-0 rounded-full bg-muted p-1.5 text-muted-foreground hover:bg-destructive/10 hover:text-destructive transition-colors"
+                        title="停止回答"
+                      >
+                        <Square className="size-3.5 fill-current" />
+                      </button>
+                    ) : input.trim() ? (
+                      <button
+                        type="submit"
+                        className="shrink-0 rounded-full bg-primary p-1.5 text-primary-foreground hover:bg-primary/90 transition-colors"
+                        title="发送"
+                      >
+                        <ArrowUp className="size-3.5" />
+                      </button>
+                    ) : null}
                   </form>
 
                   {/* 空状态提示 */}
@@ -713,7 +778,6 @@ export default function StudioNotebookDetailPage({
                   disabled={isStreaming}
                   className="flex-1 bg-transparent text-[15px] text-foreground placeholder:text-muted-foreground outline-none disabled:opacity-50"
                 />
-                {isStreaming && <Loader2 className="size-4 shrink-0 animate-spin text-muted-foreground" />}
                 {models.length > 0 && (
                   <Select value={selectedModel} onValueChange={setSelectedModel}>
                     <SelectTrigger className="h-7 w-auto shrink-0 gap-1 rounded-full border-0 bg-transparent px-2 text-sm text-muted-foreground shadow-none focus:ring-0 hover:bg-muted/60">
@@ -728,6 +792,24 @@ export default function StudioNotebookDetailPage({
                     </SelectContent>
                   </Select>
                 )}
+                {isStreaming ? (
+                  <button
+                    type="button"
+                    onClick={handleStop}
+                    className="shrink-0 rounded-full bg-muted p-1.5 text-muted-foreground hover:bg-destructive/10 hover:text-destructive transition-colors"
+                    title="停止回答"
+                  >
+                    <Square className="size-3.5 fill-current" />
+                  </button>
+                ) : input.trim() ? (
+                  <button
+                    type="submit"
+                    className="shrink-0 rounded-full bg-primary p-1.5 text-primary-foreground hover:bg-primary/90 transition-colors"
+                    title="发送"
+                  >
+                    <ArrowUp className="size-3.5" />
+                  </button>
+                ) : null}
               </form>
             </div>
 
@@ -771,6 +853,7 @@ export default function StudioNotebookDetailPage({
               sources={sources}
               isLoadingSources={isLoadingSources}
               selectedSourceIds={selectedSourceIds}
+              pendingSources={pendingSources}
               onToggle={handleToggleSource}
               onDelete={handleDeleteSource}
             />